Automobile-tire



R. L. PRUDHOMME.

AUTOMOBILE TIRE.

APPLICATION FILED AUG-9. 1919.

Patented June 1, 1920.

H "mm" un ,72 11/ III . siding 'UNITED ATENT, OFFICE. 4

I i ROBERT L. PRUDHOMME, OF NATCHITOCHES, LOUISIANA.

AUTOMQIBILE-TIRE.

Specification of Letters Patent.

7] Application filed August 9, 1919; Serial No. 316,382.

atchitoches and State of Louisiana, have invented certain new and usefulImprovements in Automobile 7 Tire hereby declare the following to be afull,

clear, and exact description of the invention, such as will enableothers skilled in the art to which it use the same.

The present invention relates ,to improveappertains to make and ments inpneumatic tires for automobiles,

and conslsts more particularly in an improved inner tube having separatechambers, one of which is inflated to normally support the vehicle,while the other may be collapsed and only inflated in the emergencieswhere, for instanoe, the first chamber becomes punctured.

In the accompanying drawings forming a part of this application, and inwhich similar reference symbols indicate corresponding parts in theseveral views:

Figure l is a perspective View of-;a section of an inner tubeconstructed in accordance with the present'invention.

Fig. 2is a similar view shown partly in longitudinal section.v

F ig; 3 is a cross'sectional view taken'on the line 3-3 in Fig. 2; and IFig. 4 is a similar view taken on the line 44 in Fig. 2.

Referring more particularly. to the draw-- ings, 1 designates an innertube, which may be identical in all substantial respects with innertubes as at the present time constructed and in use, with the exceptionthat, in accordance with the present invention, said inner tube 1 isprovided with'a partition 2 that is intended to divide same into outerand inner circumferentially extending chambers 3 and 4. I

The partition 2 is also made of the same rubber with the inner tube 1,and the edges of the partition merge with the side walls of the innertube substantially midway between 'the base and tread of such tube, asclearly shown in the drawings, so that such partition 2 divides the tubeas nearly as practicable into two equal compartments.

This partition 2 is formed of an increased thickness in the central ortread part thereof, or in otherwords reinforced with suitable materialand harder .on the outer and I -do- Patented June 1, 1920.

surface, and toward the sides of the' parof various sizes and depths andwhich are intended to break the stiffness of the par-1 tition and avoidstrain on the material of which the same is constructed.

The valve stem 6 is furnished for supplying air .tothe outer chamber 3,and a second .valve stem 7 is used to supply air to the inner chamber 4.As shown in Figs. 2 and 3, the valve stem 7 communicates directly withthe inner chamber 4 in the manner that valve stems at the present timeareconnected withinner tubes; but the valve stem 6 must be secured tothe base of the inner tube 1 and at'the same time supply air to thechamber 3 above the partition 2, so that it becomes necessary to provideaslot 8 and channel 9 within the.

inner tube 1, the air passing laterally through this channel to chamber3, the slot and channel being formed by additional thicknesses 10 of therubber at theplaceswhere the slot and channel are wanted, and the slotand channel are formed between the additional thicknesses 10and thenormal wall of the inner tube 1. The.chan

nel 9, as indicated in Fig. 2, opens upwardly into the outer chamber 3and delivers the air thereto necessary for inflation.

In use the valve stem 6 is employed to inflate the outer chamber 3, andthe inner tube is in the condition shown in Fig. 1. Here the outerchamber 3 is inflated and the partition 2 collapsed against the base of,i the inner tube 1.

The 'outer chamber 3, therefore, normally sustains theweight of the shoeand vehicle resting thereon, and this condition continues until theinner tube 1 becomes punctured or develops a leak. In case of suchemergencies the inner chamber 4 may be inflate by connecting the valvestem 7 to a pump, and the inflation of this inner chamber 4 causes thepartition 2 to move. out of the collapsed position shown in Fig.1 and upagainst the tread portion of the inner tube 1, as shown in tube 1',andwhich may sustain the vehicle until a garage or service station isreached, whereupon the punctured tread of the inner tube 1 may berepaired.

It will therefore be seen that the improved tire eliminates thenecessity of changing or repairing a tire at the time of puncture orcollapse from other causes,

but provides for the immediate re-inflation of the tire. .7

The double thickness in the base of the inner tube 1, which occurs fromthe presence of the partition 2, tends to eliminate.

rim cuts, which are quite common occurrences in tubes as used at thepresent time.

By inflating the inner chamber 4 slightly while the outer chamber '3 isin use, as

shown in Fig. 1, the air in this inner cham her 4, although slight,would support the inner tube as soon as the outer chamber v3 becamepunctured and before the mo .torist could stop. This eliminates thepossibility .of injury from running, even though :a short distance, on aflat tire.

It is obvious that those skilled in the art may vary the details ofconstruction and arrangements of parts without departing from the spiritof my invention, and there fore I do not wish to be limited to suchfeatures except as may be required by the.

claim." 2 t I claim: An inner tube'for use 1n pneumatlc tires,

comprising a continuous expansible tube, a

continuous flexible partition mounted on the inside of said tube andhaving its'opposite edges secured, to and forming an air-tight jointwith the opposite inner walls of said tube, whereby said tube is dividedto two separate concentric annular'chamers, the one exterior to theother, and'said partition being crescent-shaped in cross section andhaving its greatest thickness midway betweenthe edges thereof, saidpartition being also provided with annular grooves in the outer wallthereof to render it more flexible, with means for inserting air undercompression into said tube at either side of said partition, as desired,whereby the thickened portion of said partition may becaused to foldinwardinto the inoperative position, or maybe pressed outward intoengagement with the inner wall of the tread portion of said tube,substantially as described.

ROBERT L. PRUDHo-MME.

